mynewt-newt: 1.0.0 -> 1.3.0

Semi-automatic update. These checks were performed:

- built on NixOS
- ran `/nix/store/cjkfm1v60ykkmnqbpwc5ikhrrghklj1n-mynewt-newt-1.3.0-bin/bin/newt -h` got 0 exit code
- ran `/nix/store/cjkfm1v60ykkmnqbpwc5ikhrrghklj1n-mynewt-newt-1.3.0-bin/bin/newt --help` got 0 exit code
- ran `/nix/store/cjkfm1v60ykkmnqbpwc5ikhrrghklj1n-mynewt-newt-1.3.0-bin/bin/newt help` got 0 exit code
- ran `/nix/store/cjkfm1v60ykkmnqbpwc5ikhrrghklj1n-mynewt-newt-1.3.0-bin/bin/newt version` and found version 1.3.0
- ran `/nix/store/cjkfm1v60ykkmnqbpwc5ikhrrghklj1n-mynewt-newt-1.3.0-bin/bin/newtmgr -h` got 0 exit code
- ran `/nix/store/cjkfm1v60ykkmnqbpwc5ikhrrghklj1n-mynewt-newt-1.3.0-bin/bin/newtmgr --help` got 0 exit code
- ran `/nix/store/cjkfm1v60ykkmnqbpwc5ikhrrghklj1n-mynewt-newt-1.3.0-bin/bin/newtmgr help` got 0 exit code
- found 1.3.0 with grep in /nix/store/cjkfm1v60ykkmnqbpwc5ikhrrghklj1n-mynewt-newt-1.3.0-bin
- found 1.3.0 in filename of file in /nix/store/cjkfm1v60ykkmnqbpwc5ikhrrghklj1n-mynewt-newt-1.3.0-bin

cc "@pjones @ehmry @lethalman"